With a rapid development of rail transit, a running speed of a train is faster and faster, at a same time of getting a more convenient travel, a harm caused by an accident is also heavier and heavier, especially when the train is running on an open rail in a country field, due to a lack of fence protection, a plurality of wild animals may go to the rail at any time, especially the wild animals with a relatively large body, such as a wild boar, a wild dog or else, which may cause a great threat to a safe running of the train. Therefore, at a same time of improving a reliability of an active control, a passive security and protection is also more and more important. In order to relieve a huge damage to a body structure of the train caused by a collision between a rail transit vehicle and an obstacle, usually a cowcatcher is arranged on each of both front and back ends of the train.
The cowcatcher of a rail vehicle, in a traditional format, commonly adopts a structural format of steel plate welding, such a cowcatcher usually has a pretty high rigidity on structure, at a collision, an impact will be transferred directly to an underframe of the train, which owns a very huge peak value during the collision instantaneously, and once it exceeds a yield limit of a body material of the vehicle, an irreparable damage to the train body will be generated, which may not only fail to remove the obstacle, but also cause the cowcatcher fall off during the collision.
There is also a retractable style cowcatcher, including a flange and an energy absorption tube being able to deform under a radial pressure, whose work principle is, when the retractable style cowcatcher hits an obstacle, the energy absorption tube moves back axially, and deforms radically under the pressure to absorb the energy of impaction. On one hand, two retractable style cowcatchers are arranged at each of both front and back ends of the train, right above the rails, which owns a relatively small range of energy absorption, may only clean obstacles in small sizes, and follow an axial direction; on an other hand, the retractable style cowcatcher needs to move backwards during working, thus, it is needed to preserve a certain room at the back end, which wastes a space structure.
Therefore, the current technology needs to be improved and developed.